JPH01195738A - Picture information transmission system - Google Patents

Picture information transmission system

Info

Publication number
JPH01195738A
JPH01195738A JP63020831A JP2083188A JPH01195738A JP H01195738 A JPH01195738 A JP H01195738A JP 63020831 A JP63020831 A JP 63020831A JP 2083188 A JP2083188 A JP 2083188A JP H01195738 A JPH01195738 A JP H01195738A
Authority
JP
Japan
Prior art keywords
circuit
line
image information
channel
message
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP63020831A
Other languages
Japanese (ja)
Other versions
JP2785935B2 (en
Inventor
Keizo Minamimura
南村 恵三
Akira Arutaki
明良 阿留多伎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP63020831A priority Critical patent/JP2785935B2/en
Publication of JPH01195738A publication Critical patent/JPH01195738A/en
Application granted granted Critical
Publication of JP2785935B2 publication Critical patent/JP2785935B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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  • Data Exchanges In Wide-Area Networks (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Use Of Switch Circuits For Exchanges And Methods Of Control Of Multiplex Exchanges (AREA)

Abstract

PURPOSE:To enable a switched line network less than 64kbps to be used by providing a means to multiplex-separate picture information to follow the interface of a digital subscriber line of (2B+D), a means to realize the protocol of a D channel, and a means to guarantee the orderliness of the picture information. CONSTITUTION:A speech path for every B channel is set, and the speech path of 2B is set per one line. Such operation is repeated for a prescribed number of interfaces. Next, a message is delivered between pattern generation circuits (5-7) for B1 and a pattern detection circuit, and the transmission of the picture information which passes the switched line network is performed between a separation circuit 4 at an outgoing side and a multiplex circuit 34 at a reception side as keeping the orderliness of the speech path. Thus, by enabling connection to an ISDN converter to be performed by multiplex-separating the picture information, it is possible to perform the transmission of information by using the switched line network less than 64kbps instead of a dedicated line.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、公衆網を利用する画像情報伝送方式本発明は
、画像情報を伝送する手段において、画像情報を多重分
離してISDN交換機との接続を可能にすることにより
、 専用線に代り54kbps以下の公衆網を利用して情報
伝送を実現することができるようにしたものである。
Detailed Description of the Invention [Field of Industrial Application] The present invention provides an image information transmission system using a public network. By enabling this connection, it is possible to realize information transmission using a public network of 54 kbps or less instead of a dedicated line.

〔従来の技術〕[Conventional technology]

従来、この種の画像情報伝送方式では、画像情報の伝送
に専用線が必要であった。
Conventionally, this type of image information transmission system requires a dedicated line to transmit image information.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

このような従来の画像情報伝送方式は専用線が必要なの
で、経済的にシステムを構成できない欠点がある。
Since such a conventional image information transmission method requires a dedicated line, it has the disadvantage that the system cannot be constructed economically.

本発明はこのような欠点を除去するもので、専用線に代
り公衆網を利用する画像情報伝送方式を提供することを
目的とする。
The present invention aims to eliminate such drawbacks and provides an image information transmission system that uses a public network instead of a dedicated line.

〔問題点を解決するための手段〕[Means for solving problems]

本発明は、伝送信号が(2B+D)形式のディジタル回
線の基本インタフェースの複数個を収容するISDN交
換機の複数個と、このISDN交換機に接続され、伝送
速度が54kbps以下の公衆網と、画像情報を相互に
授受する端末とを備えた画像情報伝送方式において、上
記端末が授受する画像情報を多重または分離してこの端
末と上記基本インタフェースとを結合する多重分離手段
と、メツセージをDチャネルを経由して授受し、この多
重分離手段を経由して分割された画像情報が通過する複
数個のインタフェースを順次選択設定する設定手段と、
B、チャネル対応に設けられ、この設定手段が選択設定
するインタフェースの順序性を保証するパターン信号の
発生および検出手段を有する順序性保証手段とを備えた
ことを特徴とする。
The present invention provides a plurality of ISDN exchanges accommodating a plurality of basic interfaces of digital lines in which transmission signals are in the (2B+D) format, a public network connected to the ISDN exchanges and having a transmission speed of 54 kbps or less, and image information. In an image information transmission system comprising terminals that exchange information with each other, a demultiplexing means multiplexes or demultiplexes image information exchanged between the terminals and connects the terminals with the basic interface; a setting means for sequentially selecting and setting a plurality of interfaces through which the divided image information passes through the demultiplexing means;
B. An order guarantee means provided corresponding to each channel and having means for generating and detecting a pattern signal for guaranteeing the order of the interfaces selected and set by the setting means.

〔作用〕[Effect]

Bチャネルの1個分づつ通話路が設定され、−回線につ
き2B分の通話路が設定される。この動作が所定個のイ
ンタフェースについて繰返えされる。つぎに、Bl用パ
ターン発生回路とパターン検出回路との間にメツセージ
が授受されて通話路の順序性を保ちながら、発側の分離
回路と受側の多重回路との間で公衆網を経由する画像情
報の伝送が行われる。
A communication path is set for each B channel, and a communication path for 2B is set for each - line. This operation is repeated for a predetermined number of interfaces. Next, messages are exchanged between the Bl pattern generation circuit and the pattern detection circuit, and while maintaining the order of the communication path, the messages are transmitted between the originating side separation circuit and the receiving side multiplex circuit via the public network. Image information is transmitted.

〔実施例〕〔Example〕

以下、本発明の一実施例を図面に基づき説明する。図は
、この実施例の構成を示すブロック構成図である。
Hereinafter, one embodiment of the present invention will be described based on the drawings. The figure is a block configuration diagram showing the configuration of this embodiment.

この実施例は、図に示すように、(2B+D)チャネル
の基本インタフェースの複数個を収容するISDN交換
機2および3と、このISDN交換機2および3に接続
され、伝送速度が64kbps以下の公衆網1と、端末
が授受する画像情報を多重または分離してこの端末と上
記基本インタフェースとを結合する多重分離手段4およ
び23と、メツセージをDチャネルを経由して授受し、
この多重分離手段を経由して分割された画像情報が通過
する複数個のインタフェースを順次選択設定する設定手
段26、.34および24′、 、34′ と、B。
As shown in the figure, this embodiment includes ISDN exchanges 2 and 3 that accommodate a plurality of basic interfaces of (2B+D) channels, and a public network 1 that is connected to these ISDN exchanges 2 and 3 and has a transmission speed of 64 kbps or less. and demultiplexing means 4 and 23 for multiplexing or demultiplexing image information sent and received by the terminal and coupling this terminal to the basic interface, and sending and receiving messages via the D channel,
Setting means 26, . 34 and 24', 34' and B.

チャネル対応に設けられ、この設定手段が選択設定する
インタフェースの順序性を保証するパターン信号の発生
および検出手段を有する順序性保証手段5、 、lOお
よび17、・、22とを備える。
It is provided with sequence guarantee means 5, 10, 17, .

すなわち、ISDN交換wI2および3の各々はISD
Nベ一シツクアクセス加入者をSインタフェースをもつ
3回線を介して収容し、64kbps以下の交換が可能
な公衆網1に接続される。この実施例では、3回線であ
るが、公衆網の交換単位が64kbps以下であればそ
れに対応して3回線以上の■SDN加入者を必要とする
。また、この実施例では、発側に画像情報伝送のための
分離回路を備え、受側に画像情報伝送のための多重回路
を備えるが、実際は多重および分離回路を両側に備える
。また、メツセージの発生および検出手段はQ931 
に従うメツセージをDチャネル上に送受信し、通話路を
制御する。
That is, each of the ISDN exchanges wI2 and 3 is an ISD
It accommodates N basic access subscribers via three lines with an S interface and is connected to a public network 1 capable of switching at 64 kbps or less. In this embodiment, there are three lines, but if the switching unit of the public network is 64 kbps or less, three or more lines will be required for SDN subscribers. Further, in this embodiment, a separation circuit for transmitting image information is provided on the transmitting side, and a multiplexing circuit for transmitting image information is provided on the receiving side, but in reality, multiplexing and demultiplexing circuits are provided on both sides. Also, message generation and detection means are Q931
It sends and receives messages on the D channel and controls the communication path.

次に、384 kbpsの画像伝送速度を必要とする画
像端末が収容されているISDN交換網2を公衆網1経
由で他のISDN交換網3に接続されている画像端末に
接続する方法を説明する。制御回路34の指令に基づき
Dチャネル上りの回線選択回路24は回線1を選択する
。制御回路34の指令に基づきDチャネル上りのメツセ
ージ送出選択回路26の人力にDチャネル上りの送信用
発信回路28が接続され、発呼メツセージが回線1用2
B+D多重回路11を経由してISDN交換網2に送出
される。
Next, we will explain how to connect the ISDN switching network 2, which accommodates video terminals that require a video transmission rate of 384 kbps, to video terminals connected to other ISDN switching networks 3 via the public network 1. . Based on the command from the control circuit 34, the D channel uplink line selection circuit 24 selects line 1. Based on the command from the control circuit 34, the D channel upstream transmission transmission circuit 28 is connected to the D channel upstream message transmission selection circuit 26, and the outgoing message is sent to the line 1 and 2.
It is sent to the ISDN switching network 2 via the B+D multiplex circuit 11.

ISDN交換網2では、回線1から発呼検出後に回線1
に対して発呼に対する応答メツセージを返送し、そのメ
ツセージに基づきB1またはB2の指定が行われる。一
方、ISDN交換網2は公衆網1へのアウトゴイング:
l −/L/ (Outgoing Call)を行う
。ISDN交換M3は公衆網lからのインカミング:I
−ル(Incoming Ca1l)の検出を行って、
回線1に対して着呼メツセージを送出する。制御回路3
4′の指令に基づきDチャネル下りの回線選択回路25
は回線1を選択して、Dチャネル下りのメツセージ分離
回路27′を経由してDチャネル下り受信用の着信検出
回路31′で着呼メツセージを検出し、制御回路34′
 に報告する。制御回路34′の指令に基づきDチャネ
ル上りのメツセージ送出選択回路26′はDチャネル上
りの送信用応答回路29′を選択し、着呼に対する応答
メツセージを回線1用2B+D分離回路14を経由して
ISDN交換網3に返送する。ISDN交換網3は着呼
に対する応答メツセージを検出すると、回線1に対して
着呼に対する応答メツセージの確認応答として確認応答
メツセージを送出する。そのメツセージに基づきB+ま
たはB2の指定が行われる。このメツセージは回線1用
2B+D分離回路14からDチャネル下りの回線選択回
路25を経由してDチャネル下りのメツセージ分離回路
27′ に到り、このメツセージ分離回路27′で分離
され、Dチャネル下り受信用の応答検出回路32′でメ
ツセージの内容が解析されて制御回路34′に報告され
る。一方、ISDN交換網3は公衆網1に対して着信応
答を返送する。さて、発側の方では、発呼後にISDN
交換網22から発呼に対する応答メツセージが返送され
、回線1用2B+D多重回路11からDチャネル下りの
回線選択回路24を経由してDチャネル下りのメツセー
ジ分離回路27に到り、このメツセージ分離回路27で
分離され、Dチャネル下り受信用の応答検出回路32で
メツセージの内容が解析されて制御回路34に報告され
る。さらに、ISDN交換網2は公衆網lから着信応答
を受信し、回線1に対して着呼応答メツセージを送出す
る。このメツセージは、回線1用2B+D多重回路11
からDチャネル下りの回線選択回路24を経由してDチ
ャネル下りのメツセージ分離回路27に到り、このメツ
セージ分離回路27で分離され、受信用の応答検出回路
32でメツセージの内容が解析されて制御回路34に報
告される。このようにしてBチャネル1個分の通話路が
設定される。さらに、回線1で同様に発呼を繰り返し、
回線1の2B分の通話路が設定される。ひきつづき、回
線2と回線3とで繰り返し発呼を行って計6B分の通話
路が設定される。そのときに回線設定はDチャネル上り
の回線選択回路24およびDチャネル下りの回線選択回
路25で行う。
In ISDN switching network 2, after a call is detected from line 1,
A response message to the call is sent back to the caller, and B1 or B2 is designated based on the message. On the other hand, ISDN exchange network 2 outgoes to public network 1:
Perform l −/L/ (Outgoing Call). ISDN exchange M3 is incoming from public network I: I
- Detection of Incoming Ca1l,
Sends an incoming call message to line 1. Control circuit 3
4', the D channel downlink line selection circuit 25
selects line 1, detects an incoming message in the incoming call detection circuit 31' for D channel downlink reception via the D channel downlink message separation circuit 27', and then the control circuit 34'
Report to. Based on the command from the control circuit 34', the D channel upstream message transmission selection circuit 26' selects the D channel upstream transmission response circuit 29', and sends a response message to the incoming call via the 2B+D separation circuit 14 for line 1. It is returned to the ISDN switching network 3. When the ISDN switching network 3 detects a response message to the incoming call, it sends an acknowledgment message to the line 1 as an acknowledgment of the response message to the incoming call. Based on the message, B+ or B2 is designated. This message goes from the 2B+D separation circuit 14 for line 1 to the D channel downlink message separation circuit 27' via the D channel downlink line selection circuit 25, and is separated by the D channel downlink message separation circuit 27', and is received by the D channel downlink message separation circuit 27'. The content of the message is analyzed by the response detection circuit 32' and reported to the control circuit 34'. On the other hand, the ISDN exchange network 3 returns an incoming call response to the public network 1. Now, on the calling side, after making the call, the ISDN
A response message to the call is returned from the switching network 22, and is sent from the 2B+D multiplexing circuit 11 for line 1 via the D channel downstream line selection circuit 24 to the D channel downstream message separation circuit 27. The contents of the message are analyzed by the response detection circuit 32 for D channel downlink reception and reported to the control circuit 34. Further, the ISDN switching network 2 receives an incoming call response from the public network l and sends an incoming call response message to the line 1. This message is sent to the 2B+D multiplex circuit 11 for line 1.
The message goes through the D channel downstream line selection circuit 24 to the D channel downstream message separation circuit 27, is separated by the message separation circuit 27, and the reception response detection circuit 32 analyzes the contents of the message and controls the message. is reported to circuit 34. In this way, a communication path for one B channel is established. Furthermore, the call is repeated in the same way on line 1,
A communication path for 2B of line 1 is set. Subsequently, calls are made repeatedly on line 2 and line 3, and a total of 6B worth of communication paths are established. At this time, line setting is performed by the D channel upstream line selection circuit 24 and the D channel downstream line selection circuit 25.

つぎに、6Bの順序性を検証するために発側の回線10
81用パターン発生回路5、回線2のB。
Next, in order to verify the orderliness of 6B, the originating line 10
81 pattern generation circuit 5, line 2 B.

用パターン発生回路6および回線30B+用パタ一ン発
生回路7からパターンを発生して着信の回線1081用
パターン検出回路20、回線2のB。
A pattern is generated from the pattern generating circuit 6 for the incoming call and the pattern generating circuit 7 for the line 30B+, and the pattern detecting circuit 20 for the incoming call line 1081 and the B of the line 2.

用パターン検出回路21および回線3のB、用パターン
検出回路22でパターンを検出、パターン検出可能なよ
うに回線1の81と82との切替用2X2スイツチ17
、回線2のB+ とB2との切替用2x2スイツチ18
および回線3のB+ とB2との切替用2×2スイツチ
19を制御する。つぎに着側のBt用パターン発生回路
5.6および7からパターンを発生して、発側のパター
ン検出回路20.21および22でパターンを検出し、
切替用2X2スイツチ17.18および19を制御する
。このようにして通話路の順序性を保証し分離・速度変
換回路4と多重・速度変換回路23とで一定の順序性を
持って多重分離して画像情報の伝送を可能にする。
The 2X2 switch 17 for switching between 81 and 82 of line 1 detects the pattern with the pattern detection circuit 21 of line 3 and the pattern detection circuit 22 of line 3.
, 2x2 switch 18 for switching between B+ and B2 of line 2
And controls the 2×2 switch 19 for switching between B+ and B2 of line 3. Next, a pattern is generated from the Bt pattern generation circuits 5.6 and 7 on the destination side, and the pattern is detected by the pattern detection circuits 20.21 and 22 on the origination side.
Controls 2X2 switches 17, 18 and 19. In this way, the order of the communication path is guaranteed, and the demultiplexing/speed converting circuit 4 and the multiplexing/speed converting circuit 23 demultiplex and demultiplex with a certain order, making it possible to transmit image information.

〔発明の効果〕〔Effect of the invention〕

本発明は以上説明したように、画像情報を2B+Dのデ
ィジタル加入者回線のインタフェースに準拠するための
多重分離する手段とDチャネルプロトコルを実現する手
段と画像情報の順序性を保証する手段とが設けられてい
るので、2B+Dのディジタル加入者回線のインタフェ
ース(Sインタフェース)を複数具備でき、また画像伝
送のために専用線を必要とせず、54kbps以下の公
衆網を利用することができる効果がある。
As explained above, the present invention includes means for demultiplexing image information in order to comply with the 2B+D digital subscriber line interface, means for realizing the D channel protocol, and means for guaranteeing the order of the image information. Therefore, it is possible to have a plurality of 2B+D digital subscriber line interfaces (S interfaces), and there is no need for a dedicated line for image transmission, making it possible to use a public network of 54 kbps or less.

【図面の簡単な説明】[Brief explanation of the drawing]

図は本発明実施例の構成を示すブロック構成図。 1・・・公衆網、2.3・・・ISDN交換網、4・・
・分離・速度変換回路、5.6.7・・・B、用パター
ン発生回路、8.9.10・・・切替用選択回路、11
・・・回線1用2B+D多重回路、12・・・回線2用
2B+D多重回路、13・・・回線3用2B+D多重回
路、14・・・回線1用2B+D分離回路、15・・・
回線2用2B+D分離回路、16・・・回線3用2B+
D分離回路、17.18.19・・・切替用2X2スイ
ツチ、23・・・多重・速度変換回路、24.25・・
・回線選択回路、26.26′・・・メツセージ送出選
択回路、27.27′・・・メツセージ分離回路、28
.28′・・・送信用発信回路、29.29′・・・送
信用応答回路、30.30′・・・送信用切断回路、3
1.31′・・・着信検出回路、32.32′・・・応
答検出回路、33.33′・・・切断検出回路、34.
34′・・・制御回路。 ″−4汎二
The figure is a block configuration diagram showing the configuration of an embodiment of the present invention. 1...Public network, 2.3...ISDN switched network, 4...
- Separation/speed conversion circuit, 5.6.7...B, pattern generation circuit, 8.9.10... switching selection circuit, 11
...2B+D multiplex circuit for line 1, 12...2B+D multiplex circuit for line 2, 13...2B+D multiplex circuit for line 3, 14...2B+D separation circuit for line 1, 15...
2B+D separation circuit for line 2, 16...2B+ for line 3
D separation circuit, 17.18.19... 2X2 switch for switching, 23... Multiplex/speed conversion circuit, 24.25...
・Line selection circuit, 26.26'...Message sending selection circuit, 27.27'...Message separation circuit, 28
.. 28'... Transmission oscillation circuit, 29.29'... Transmission response circuit, 30.30'... Transmission disconnection circuit, 3
1.31'...Incoming call detection circuit, 32.32'...Response detection circuit, 33.33'...Disconnection detection circuit, 34.
34'...control circuit. ″−4 Panji

Claims (1)

【特許請求の範囲】 1、伝送信号が(2B+D)形式のディジタル回線の基
本インタフェースの複数個を収容するISDN交換機の
複数個と、 このISDN交換機に接続され、伝送速度が64kbp
s以下の公衆網と、 画像情報を相互に授受する端末と を備えた画像情報伝送方式において、 上記端末が授受する画像情報を多重または分離してこの
端末と上記基本インタフェースとを結合する多重分離手
段と、 メッセージをDチャネルを経由して授受し、この多重分
離手段を経由して分割された画像情報が通過する複数個
のインタフェースを順次選択設定する設定手段と、 B_1チャネル対応に設けられ、この設定手段が選択設
定するインタフェースの順序性を保証するパターン信号
の発生および検出手段を有する順序性保証手段と を備えたことを特徴とする画像情報伝送方式。
[Scope of Claims] 1. A plurality of ISDN exchanges accommodating a plurality of basic interfaces of digital lines in which transmission signals are in the (2B+D) format; and a plurality of ISDN exchanges connected to the ISDN exchanges and having a transmission speed of 64 kbp.
In an image information transmission system equipped with a public network of s or less and a terminal that exchanges image information with each other, a demultiplexing method that multiplexes or separates the image information exchanged by the terminal and connects this terminal with the basic interface described above. means, a setting means for sequentially selecting and setting a plurality of interfaces through which messages are exchanged via the D channel and image information divided via the demultiplexing means passes; and a setting means provided corresponding to the B_1 channel; 1. An image information transmission system comprising: order guarantee means having pattern signal generation and detection means for guaranteeing the order of the interfaces selected and set by the setting means.
JP63020831A 1988-01-29 1988-01-29 Image information transmission device Expired - Lifetime JP2785935B2 (en)

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JP63020831A JP2785935B2 (en) 1988-01-29 1988-01-29 Image information transmission device

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JPH01195738A true JPH01195738A (en) 1989-08-07
JP2785935B2 JP2785935B2 (en) 1998-08-13

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04223673A (en) * 1990-12-25 1992-08-13 Canon Inc Transmitting device
JPH05235934A (en) * 1991-08-29 1993-09-10 Internatl Business Mach Corp <Ibm> Device for connecting data communication equipment to digital communication network

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04223673A (en) * 1990-12-25 1992-08-13 Canon Inc Transmitting device
JPH05235934A (en) * 1991-08-29 1993-09-10 Internatl Business Mach Corp <Ibm> Device for connecting data communication equipment to digital communication network

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JP2785935B2 (en) 1998-08-13

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